1. Field of the Invention
The invention according to the present application relates to soluble trauma-healing blood-stilling cellulose containing coagulation protein and a method of preparation thereof, and more specifically to an internally absorbing soluble wound-covering blood-stilling material promoting blood coagulation and vascular dilation on application to the internal or external lesion and a method of preparation thereof.
2. Description of the Related Art
In the past there types of traumato-hemostatic agent, namely cellulose oxide, gelatin and micro-fibrous collagen, have been known and have already been used as medical preparations and for medical instruments. Cellulose oxide agents achieve their hemostatic action in that the anhydrous polygluconic acid has an extremely strong affinity to hemoglobin and forms a salt with it. This hemo-coagulation promoting effect is due not so much to the agent's action on the blood's coagulation mechanism but rather to physical action. That is to say, that this agent promotes the formation of blood coagulates as the result of the perfusion of blood causing this agent to swell with the development of brown or black gelatin clots. The agent thus displays an ancillary localized hemostatic action and is absorbed in approximately two weeks. Furthermore, microfibrous collagen contains as the main component natural collagen extracted from the bovine dermis and achieves a hemostatic action through platelet agglutination on contact with blood.
Since the cellulose oxide agent does not directly act on the blood coagulation system it has a weak coagulating effect and thus requires approximately two weeks to be completely absorbed in the system so that it acts as an inflammation and adhesion promoting factor in the affected area during this period. Gelatin agents have a slower absorption than cellulose oxide and are animal derived materials so that there is a considerable possibility of their causing various infectious diseases, including mad cows disease and Kreutzfeld Jakob disease. Moreover, microfibrous collagen takes about a month or longer to be completely absorbed so that it is liable to cause inflammation and adhesion in the affected part during this period. Since the agent is of bovine origin there it carries a risk of infectious diseases such as mad cows disease or or other infections due to unknown viruses.
Hemostasis with the conventional methods using the above hemostatic agents is apt to lead to inflammation and adhesion due to the poor internal absorption of these agents and carries a risk of disease due to unknown infections.
Furthermore, the Japanese Patent Laid-Open No. Hei10-77571 refers to a soluble cellulose fiber whose hydroxyl groups in the glucose units constituting the cellulose molecules of the natural or regenerated cellulose fibers have been partially carboxymethylated so that its etherification degree becomes 1.0% or higher and which exhibits a hemostatic effect by covering the trauma by rapidly dissolving on contact with blood and congealing to a gelatin with the blood.
When the degree of replacement of the carboxymethyl radicals (etherification degree) equals or exceeds 1.0%, however, the agent will not rapidly dissolve even when coming in contact with blood and a large amount of unusable material will remain without exhibiting a significant hemostatic effect, while, furthermore, the solubilized carboxymethyl cellulose fibers have no effect whatsoever on the enzymes of the blood coagulation system such as coagulation factor XII.
Furthermore, the Japanese Patent Application No. Hei11-58412 refers to a soluble trauma-healing hemostatic cellulose fiber whose hydroxyl groups in the glucose units constituting the cellulose molecules of the natural or regenerated cellulose fibers have been partially carboxymethylated so that its carboxymethyl substitution level (etherification degree) becomes 0.5-under 1.0%.
The aforesaid soluble trauma-healing hemostatic cellulose fiber material does rapidly dissolve on contact with blood to exhibit a very potent hemostatic effect it has a blood-stilling effect only when coming in contact with blood. Its effect is thus due to its interactions with the platelets and fibrin of the blood so that in minor hemorrhage, that is to say, in loci (trauma sites) with little platelet and fibrin amounts it has a small hemostatic effect.